1. Field of the Invention
This invention generally relates to a bicycle front derailleur. More specifically, the present invention relates to a bicycle front derailleur, which is designed to aid in an upshifting operation of a chain onto the largest sprocket of a crankset.
2. Background Information
Bicycling is becoming an increasingly more popular form of recreation as well as a means of transportation. Moreover, bicycling has become a very popular competitive sport for both amateurs and professionals. Whether the bicycle is used for recreation, transportation or competition, the bicycle industry is constantly improving the various components of the bicycle. One component that has been extensively redesigned over the past years is the bicycle drive train. Specifically, manufacturers of bicycle components have been continually improving shifting performance of the various shifting components such as the shifter, the shift cable, the derailleur, the chain and the sprocket or sprockets.
Generally, a front derailleur is mounted to the bicycle frame adjacent to the front sprockets to shift a chain laterally between the front sprockets. A front derailleur includes a fixed member non-movably secured to the bicycle frame, and a movable member with a chain guide that is movably supported relative to the fixed member to move between at least two lateral shift positions. Typically, a linkage assembly is coupled between the fixed member and the movable member in order to movably support the movable member with the chain guide. The chain guide has a pair of cage plates or guide plates arranged to selectively contact and move the chain between the front sprockets. On example of this type of conventional front derailleur is disclosed in U.S. Patent Publication No. 2008/0026889. With a front derailleur such as the one disclosed in this publication, the chain can sometimes get caught on a tip of a tooth of the largest sprocket of a crankset during an upshifting operation.